Hair bleaching is a well known process in the hair cosmetic field. Hair bleaching involves the application of an oxidizing agent to the hair for a period of time effective to achieve a desired lighter hair shade. The oxidizing agent typically is a hydrogen peroxide solution in concentrations ranging from 3 to 12% by weight. The hydrogen peroxide is applied to the hair under alkaline pH conditions and gradually lightens the shade of the hair by oxidizing the melanin that gives it color. 28% Ammonium hydroxide is typically added to the peroxide solution at the time of use to provide the highly alkaline environment needed during use.
To enhance the lightening efficacy of the hydrogen peroxide oxidizer, it is known to incorporate a persulfate salt as a “booster”. Sodium, potassium, and ammonium persulfate salts, and mixtures thereof are provided in powder form, and are admixed with the hydrogen peroxide solution and the ammonium hydroxide solution at the time of use. The mixed product is then applied to the hair for a period of time effective to achieve the desired lighter hair shade. Because of the incorporation of the persulfate and when used with a 10 to 40% by volume hydrogen peroxide solution activated by the alkalizing agent, e.g., 28% ammonium hydroxide, substantial lightening of hair can be achieved. Such products are typically sold in kit form comprising the three part system comprising the peroxide, activator and alkaline compositions that are admixed at the time of use for form a hair bleach product composition.
The hair bleach product composition is generally applied to the hair with a brush that is dipped into the bleach product composition. To streak or highlight the hair, sections of the hair are individually treated, and the sections are then segregated from the remainder of the hair, e.g., with aluminum foil.